This invention relates generally to coin handling machines, and specifically to coin handling machines with rotating coin bowls.
Referring to FIG. 1, shown is a plan view of a conventional coin handling machine having a coin bowl 10 which may be at an angle to horizontal and is typically rotated. Coins are typically loaded into the machine through a fixed coin hopper 20 and fall gravitationally, or are pushed into the coin bowl. (Coin 12a is shown leaving the coin bowl, while coin 12b is shown lodged in a coin receiving space.) The coins form a tumbling coin mass and coin lifters 14 attached to a rotating drum wheel disk 16 help direct coins through coin receiving holes 17 of the drum wheel disk when the coin level is low and into the space between the back side of the drum wheel disk and a stationary surface which is parallel and spaced from the drum wheel disk. The drum wheel disk forms the bottom of the coin bowl 10 and carries ejector pins 19 on its back side which direct the coins to an exit chute 18. A coin stripper 22, mounted on a stationary back surface 24 and positioned behind the drum wheel disk, engages an edge of a coin as it is pushed along by the ejector pins and directs the coins into chute 18 and out of the machine. The coins impinge on a coin stripper edge 22a, which is usually a hard steel or plastic surface. Ejector pins 19 exert forces on the coins which act both parallel and perpendicular to the coin stripper edge. A hub 25 on the back side of drum wheel disk 16 may also be included to help guide the flow of coins toward coin holes 17.
Other coin handling machines which operate along the lines discussed above are known. U.S. Pat. No. Reissue No. 28,557 shows a disk dispensing apparatus. U.S. Pat. No. 902,067 (Froberg) discloses a rotating coin receiver designed to receive a mass of coins, preferably inclined so that the coins slide toward a lower portion of the coin receiver, where openings allow the coins to be driven out of the receiver by reciprocating slides. Similarly, U.S. Pat. No. 918,273 (Brewster) discloses a coin counter having a plurality of coin separating disks which rotate around a spindle and in which a hopper rotates via a hand wheel crank. U.S. Pat. No. 1,080,533 (Bach) discloses a rotating coin hopper, but coins are guided only by rotation of the hopper. Other relevant patents include U.S. Pat. No. 1,095,981, which shows a lifting plate for discharging coins; U.S. Pat. No. 3,757,805, which shows an annular ring which defines an adjustable space for coins of different thicknesses; U.S. Pat. Nos. 4,557,282 and 4,620,559, which disclose rotating coin hoppers; and U.S. Pat. No. 4,570,655 which shows coin guides.
Most prior art coin handling machines suffer frequent failures which take them out of service. Failures are typically due to a coin wedging against a stationary coin bowl ring or other surface which is stationary or relatively slower moving. Other failures typically occur because of improper or lack of adequate agitation of the coin mass by the rotating drum wheel disk and the coin lifters attached to the drum wheel disk, inadequate guidance of the coins as they are moved toward the discharge chute, or the accumulation of "coin dust" in these machines, with no apparent way of removing it.